Existing switches operate by mechanically moving parts on which mirrors or prisms, etc . . . are mounted.
Such mechanical systems suffer from the need for the moving parts to be adjusted highly accurately so that the light beam is deflected with precision. Not only does the rest position of the moving parts need adjusting with accuracy, the travel and the working position at the end of the travel also need to be adjusted accurately.
In addition to the considerable technological difficulties involved in meeting such requirements, the required accuracy leads to the resulting systems being expensive. Further, there is no guarantee that such systems will remain accurately adjusted over a period of time.
Preferred embodiments of the present invention provide an optical switch which avoids the need for such accurate adjustments, and which is therefore cheap to produce and reliable.
The invention also provides a matrix of such switches.